By Tracy Cassels
New breastfeeding news is making headlines as the lead researcher and journalists claim that breastfeeding expectations are causing depression in women. The research comes from the Murdoch Institute in Australia (the same institute known for giving us all that pro-CIO research too) and claims to show that the pressure to breastfeed is resulting in greater depression in women [1].
But does it?
We have long known that there is an inverse relationship between breastfeeding and postpartum depression with an intricate web of factors that influence this relationship (for reviews, see [2][3]). For example, we now know that prenatal depression plays a role in the early cessation of breastfeeding, but not the intention to breastfeed[4]. We also know that breastfeeding has been found to decrease the risk of post-partum depression with early cessation linked to increased risk of depression[4][5]. Finally, we also know that early cessation of breastfeeding can be the result of depression, and is not always the other way around[6].
This new research seems to want to throw all of this on its head. Which is great and intriguing if this is what they have actually found. After all, cultural attitudes can shift and result in findings that wouldn’t have made sense previously. (Of course, these other studies are also all recent so at the very least we would have conflicting findings to contend with.) The authors begin justifying the research by claiming that the previous work on breastfeeding duration and depression is “ambiguous”. I would like to point out that there is virtually nothing ambiguous about it and the researchers do not provide any evidence of it being ambiguous.
Indeed, each study they cite reports a relationship between depression and shorter breastfeeding duration. What remains unclear, however, is why.
The study recruited 1258 pregnant women with a gestation of <24 weeks during the years of 2003-2005. At this baseline, basic demographic data was collected as was a depression baseline using the Edinburgh Postnatal Depression Scale, which although is primarily validated for postnatal depression, has been validated for use in a prenatal sample as well. At three months postpartum, the depression scale as given again and at six months postpartum breastfeeding data was collected. Breastfeeding data included ‘ever breastfed’, ‘still breastfeeding’, and ‘age of cessation of breastfeeding’ variables. Please note now that at no point do we have any information on why breastfeeding ended, breastfeeding desires prenatally or postnatally, or anything to do with breastfeeding pressure.
Around 95% of women initiated breastfeeding (and these women are who are included herein for a total of 1176 women), but only 76% of them were breastfeeding at all at three months and 60% at six months. At three months, 6.5% of the women reported depression symptoms above the cutoff. The only demographic variable linked to depression at three months was whether or not the woman was employed or studying in early pregnancy, with those reporting “no” having a 94% increased risk of depression at three months.
With respect to breastfeeding, depression at three months resulted in an 82% increased risk of not breastfeeding at six months and this was after controlling for country of birth, maternal age, highest education, employment, and smoking status (many of which also independently contributed to not breastfeeding). What was interesting is that the divergence in breastfeeding rates by depression at three months did not occur until the three month period. That is, breastfeeding rates for the two groups were similar for months one and two, but at three months, we see a split in breastfeeding rates. What does this mean? We don’t know. It means that it could be that depression came first, building up in the first three months and then led to the cessation of breastfeeding or that the cessation of breastfeeding increased the risk of postpartum depression. That data fits both narratives.
But what about the claim that the push to breastfeed is harming women’s health? Well, there is absolutely nothing that suggests this.
Nada. In fact, I’m not even sure how one would logically argue this given the data at hand, but let us try to walk through this together, looking at the key points of such an argument:
- If breastfeeding pressure is resulting in postpartum depression, then we would expect to see large rates of depression in the early months because this is when the “pressure” would be strongest. This data does not provide any information on depression in months one and two, only breastfeeding rates which are similar between the group that eventually reports depression and the group that does not.
- If breastfeeding pressure results in postpartum depression, then we might expect to see either women breastfeeding and reporting not enjoying it and thus suffering or ceasing to breastfeed and reporting a relief of depressive symptoms. There is no data on any maternal report for reasons for stopping breastfeeding or any other factor to do with infant feeding either prenatally or postnatally. There is also no comparison of depressive symptoms across time with which to make a comparison.
- If breastfeeding pressure results in postpartum depression, then we might expect to see greater depression with the cessation of breastfeeding for the failure to meet the societal goal of breastfeeding. Again, we have no comparison of depressive symptoms across time with which to make a comparison.
